Field of the Invention
The invention concerns a process for producing a mold, wherein an internal space corresponding to the shape of the component to be produced is formed within a mold frame.
Molds have a massive void volume, which is substantially Larger than the volume of the hollow space for the component to be produced, which however it must be dealt with as part of the normal construction process. It is known to introduce separate form inserts to occupy part of this voluminous space. These must however be newly produced each time, for example by milling or molding.
The invention makes it possible to produce molds more rapidly and with less waste.
As filler elements, with which the rigid mold frame is filled with the exception of the area close to the hollow space, multiple identically-shaped building blocks of a solid material are used in the first embodiment of the invention. In order that the building blocks maintain their position, they could be provided with projections and/or recess, which engage form-fittingly in each other or, as the case may be, in the inner side of the mold frame. Alternatively, or additionally, the construction elements may be constructed of a ferromagnetic material, in which one produces a magnetic flux which holds these together, for example via an electromagnet, which is provided outside of the mold frame.
Since the regularly shaped building blocks can be reused repeatedly, only a relatively small amount of these construction elements is required. Only the actual mold shell, which one produces by any conventional manner, need be stored for re-use and this by itself only requires a comparatively small amount of space.
In a second embodiment of the invention the filler elements are irregularly shaped particles with a hardenable binder, for example hardenable sand. If the binder is water-soluble, then the sand can be recycled and reused.
The inventive process is particularly suitable for the production of molds for the production of fine or precision cast models, for example wax models, as well as for producing molds for plastic injection molding.